Our principle research objective is to identify the biochemical origin and physical structure of the heavy molecular weight aggregates of lens proteins which are responsible for light scattering in the aging normal lens and opacification in the cataractous lens. We shall use biochemical methods to characterize the individual proteins and the protein-protein interactions associated with the formation of both heavy molecular weight soluble protein aggregates and insoluble protein aggregates. We shall use the methods of quasi-elastic laser light scattering spectroscopy to determine quantitatively in whole intact lenses the effectiveness of various biochemical reagents which act to accelerate, inhibit, or reverse the aggregation process associated with cataractogenesis.